Towards an experimental model of anxiety for treatment development: The effects of carbon dioxide inhalation on subjective mood, autonomic arousal and neurocognitive function. Seminar

Anxiety symptoms are common in the general population, and patients with anxiety disorders have severe and persistent symptoms that cause significant personal distress, impair everyday function and reduce quality of life. Generalized Anxiety Disorder (GAD) is a severe and long-lasting condition which includes excessive and persistent anxiety and worry, difficulty concentrating and hyper-vigilance.
There is a need to improve treatments for anxiety through developing valid experimental human models of anxiety that improve on the poor predictive validity of animal models. Human models would allow us to more effectively evaluate novel pharmacological and psychological treatments (and mechanisms of action) in healthy volunteers, prior to evaluation in clinical trials with patient populations.
Inhalation of 7.5% carbon dioxide (CO2) increases feelings of anxiety and autonomic arousal, and has been proposed as a putative experimental model of generalized anxiety in healthy humans. I will present data from our recent work that shows that the CO2 model can also induce dysfunction in neuropsychological mechanisms that characterise anxiety e.g. poor attention control, hyper-vigilance and selective processing of environmental threat.
I will also present our initial findings from on-going work that is using the CO2 model to evaluate a range of treatment interventions and modalities for anxiety. These include psychological interventions (e.g. mindfulness-meditation), computerised cognitive bias modification procedures (e.g. attention training), pharmacological drug treatments, and medical devices that can target prefrontal cortical mechanisms (e.g. trans-cranial direct current stimulation).